Spree bbk issues.

[jakubman1]

Alright so my temps are 385 degrees. Cuts out while riding and hard to when hot. When it cuts off while riding it feels like it's gonna lock up but doesn't and slows me down very quick. What gives ?? Has the larger main jet. Boost port cut. And 3 . 1Inch holes on air.box lid. After cooling down starts easily . Makes some funny sounds while riding when at those temps.

[Wheelman-111]

Greetings:

Hmm... A CHT of 385 for a Spree sounds a bit high to me as well. Heat does funny things to engines. Bearing sockets enlarge - just a little. Ask anyone who's heated a crankcase and chilled the bearing. A bearing that normally needs Firm Persuasion to whack into its socket now drops in with gravity alone - I've done this - and a Sizzle. Add the fact that different metals expand at different rates. Aluminum slug in an iron cylinder - and a mismatch in diameters is easy to envision. If the piston is much smaller than its bore, it's free to "rock" a little at the top and bottom of the stroke. This or something like it may explain your noise - sometimes called Piston Slap. The same thing may be happening - to a lesser degree - in the bearing cages, especially the wrist pin.

I don't knew about the Spree big-block specifically. What was the static compression when you screwed it on? I'd shoot for 130 or less. High compression typically increases heat - a lot. Also your 3 holes probably just KILLS your negative pressure in the box, which Honda-san designed in so that the tiny Pilot would have plenty of Suction pulling fuel through it. The danger here is when the engine is revving high and you CLOSE the throttle. Without negative pressure in the carb throat, the fuel trickle dries up, along with its evaporative cooling effect on the cylinder and slug. Watch carefully for heat spikes in that situation.

[jakubman1]

I think its soft seizing. It happens at WOT and i only broke it in maybe 10 miles. I think what ill do is rebuild it with my spare BBK and take it real easy for 100 miles like iam suppose to. Fudge
Temps should be around 350-375 anything above that will soft seize.
Directions say to drill 3..1inch holes. Then i snapped in the pod filters.

[Meatball]

My bbk break-in is at about 30mi so far. However, Im taking it easy and not running over 15-18mph. It did develop a crazy sound I hadn't heard before the install. A loud rattle/vibration noise that I suspect is coming from the rear wheel bearing. I took the rear gear cover off to inspect everything and pulled the gears off. The bearing that's pressed into the rear cover seems fine. Its an open bearing and is subject to the oil bath inside the case so its constantly lubed. The one thats next to the rear wheel is very suspect. It spins fine (no play) but somehow sounds like a ball bearing is loose inside of it when I spin it. It is actually separated by an oil seal from the bath and the bearing is completely sealed on both sides of it. Theres no way to lube these sealed bearings and Im thinking its factory lube finally gave up. I have new bearings and oil seals on order as well as a set of TAZ gears! Once those come in and get installed I will let you know if that fixed it. My next thought if that doesn't help are the bearings in the clutch...theres 2 in there too.

[jakubman1]

So should i be investing in a new carb??

Iam not using Taz gears. I just swapped my belt. Does the exact same thing and easier to remove.

[Meatball]

Why not do the belt trick AND the gears? Double whammy!

[eclark5483]

Why not do the belt trick AND the gears? Double whammy!

I agree. That's what I plan on doing as well. I'm not gonna switch to the AX23 belt though till after my BBK is broken in and I have the Polini carb. I wanna run it through the Dyno a couple times to see what the difference is in performance and what my power band will be. Been searching around the forums, and this also caught my attention: http://japan.webike.net/products/373376.html Mine's also running the MLM people's pipe, so it will be very interesting to see what kind of performance one can actually expect from a new Polini, Super Tact intake, Tazland BBK, Tazland gears, MLM pipe, AX23 belt, and I MIGHT consider doing the pully mod as well. I see so many people scream ENGINE SWAP, ENGINE SWAP... CHEAPER, FASTER... YADDA YADDA!! Oh I don't doubt that for a second. Maybe I'll consider doing that on another Iowa Spree once I find one, but on this one, I wanna see what all the advice and tricks people have for that stock engine can get me. I'm not shooting for high performance/high speeds. I'm just shooting for a stock engine that performs.

[Ultraliner]

Now THAT is a cool find eclarke!!

[eclark5483]

Found it when I stumbled across this topic:

viewtopic.php?f=4&t=30071

[jakubman1]

I'm not trying to throw more money at this thing !

I asked for some advice and now have people talking about more upgrades.

I'm trying to figure what's wrong.

Is it safe to drive after soft seizing twice already?

[jakubman1]

Which size mm of compression tester will I need . There are 3 different sizes ..thanks

[Meatball]

The tester kits usually come with a few different male fittings. Even the cheap ones. The size you need is pretty standard and is included in the kit. Im not a huge fan of Harbor Freight but this kit is cheap and will be just fine for scooter readings. I just wouldn't test your Ferrari with it.

http://www.harborfreight.com/compressio ... 62638.html

[Meatball]

It happens at WOT and i only broke it in maybe 10 miles.

This also might be a factor.

[jakubman1]

Wot on a new engine will cause it to overheat ? Why is that?

[Meatball]

New piston rings rubbing against new cylinder walls that have never rubbed each other before causes excessive friction. Friction generates heat. The "break-in" period of new engine parts is generally a process of moving parts wearing against each other to produce the last small bit of size and shape adjustment that will settle them into a stable relationship for the rest of their working life. If you look at the NEW bbk cylinder wall youll see cross-hatch type marks that are made during the honing process. Look at your OLD original bore (which has seen millions of piston strokes) and its smooth with maybe some slight vertical stroke marks. The excessive friction (heat) caused by new parts is why they recommend short trips at varying low-ish RPM's so parts break-in without being subject to thermal stress.